gemini increased steering angle

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Gemi Coupe
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Post by Gemi Coupe »

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MAT713
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Post by MAT713 »

your punter will do plenty of dodgy things on the car, but thats not just for drift, it happens in every form of motorsport.

i dont really see many if any dodgy products on the higher level cars.

generally your average drift silvia in australia will have:
rose jointed adjustable toe/camber/castor arms
skylines hubs, bigger strong, larger wheel bearsings
skyline diffs in silvias
dry sump


of course your gonna copy wat the japs r doing, they r the best at it and being doing it longer then anyone else, im sure after 15 years of it and there technolgy they have learnt a thing or 2
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Post by F3ARED »

A drift setup is far from good for a race track. Generally, while the camber and spring rate setups will give good mechanical grip, changes to toe in/out etc are too agressive making the car twitchy on turn in.

Although a higher level of grip gives you a higher slip speed, you need to remember there always has to be an imbalance in the first place to allow the car to get sideways.

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damo666
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Post by damo666 »

MAT713 wrote: generally your average drift silvia in australia will have:
...
dry sump
Your average 18 year old wanabe drifter will have his CA18 Silvia dry sumped??
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Post by archangel62 »

A good drift setup is (in my opinion) pretty neutral, which is good for grip too. The difference is that a drifter might go for a 2way LSD not a 1.5 way, and would adjust the springrates and swaybars for that tiny bit more oversteer. Really, a good, non-overstated drift setup would be a slightly tail-happy grip setup, and vice versa. Anyone who can afford a good drift setup would have adjustable gear, and the skills to drift with ther driving, not s*#t grip balance etc...

So if you ask me a good drift setup is pretty close to a grip setup, just my two cents.

I'm interested in this Ackerman stuff... Even if, chances are, none of us are gonna tinker with it on our Gems solely because of the complexity and (I assume) the mechanical challenge.
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paddles
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Post by paddles »

archangel62 wrote: So if you ask me a good drift setup is pretty close to a grip setup, just my two cents.
I disagree with you on this one. A set up for a track car that results in quick lap times is typically alot softer than you would expect. Most people think that quick lap times = really big bars and really stiff spring rates, which more often that not will result in the mother of all understeer followed by snap oversteer. To make a sedan fast, I've found that they like to 'lean' quite alot on the outside tyres. I've f*#cked around with bars and rates a bit on an open track (we can book the race track for free up here 8) ) and I think that a stiff set up feels good at 80% pace, but when you really want to go fast it sucks the wang. I also like relatively soft rear spring rates with a stiffer bar which gives great traction on corner exit, I would have thought stiff rear spring rates would be necessary in drift to prevent squat.
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Post by Gemi Coupe »

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yldgem
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Post by yldgem »

ooohh, a moving diagram, thats flash! intersting aswell.
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Post by pistonbroke »

MAT713 wrote:
drifters have simply extended their racks and run longer tie rod ends to get more lock. its been tried tested and proven to work time and time again. saying that, its yet to see if proven effective on a gemini. the above formula is normally applied to the nissan drift cars.
This is what I said in the begining.If you can get someone who knows what they are on about to draw it,it does work.I thought it was B.S. until shown diagrams and explained how it works.Its just geometry.
archangel62
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Post by archangel62 »

paddles wrote:[(we can book the race track for free up here 8) )
You bastard!!! :cry: Give us your track n stuff.

I'm guessing your experience would overshadow that of a lot of us, what I've always wanted to do is just tinker with a million different suspension setups on my Gem... But I don't have the chance to. Would you be able to share some of the stuff you've tried, and results? It would be extremely appreciated...

Gemi Coupe that's an awesome diagram, is the centre part of that done in the steering rack, or is that determined by the positioning of the tie rod end mount on the hub?
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Post by paddles »

Oh it's great isn't it :lol: Make a phone call and we have the track and pit paddock all to ourselves.

To be honest I'm not sure I'd be much help, as nearly all of my set up experience is from a Datsun 1600 (IRS rear, macpherson strut front). The gem is just a daily that I keep very stiff to reduce rear grip so the arse end flicks around quickly for motorkhana's. fish would be good to talk to about gemini-specific set ups, Im sure he's tinkered with his race car alot. If you're keen I could go through a few things that I've learnt, but of course every car, driver and track is different so it certainly won't be gospel. Just my experiences. pm me if you are keen
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redzone (coxy)
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Post by redzone (coxy) »

jeez there's a few massively presumptuous opinions floating around in here.. and from people i thought would know better! maybe its just drift ignorance? people doing grip circuit racing i'm afraid dont know s*#t about the setup requirements for a drift car, they tend to assume too much.

a proper competition level drift suspension setup works exceptionally well as a grip setup, just by changing tyres and driving style, and some minor shock setting alterations. you have to remember that drift is usually instigated by handbrake, clutch kick or (high speed) sudden foot brake use to unsettle the car. NOT just "flicking the steering wheel"

case in point:

my mate stu has an R33 skyline drift car, he goes really well in drift comps at QR, all he does to change the car for the new JDM (grip) series he competes in there, is what i mentioned above. he doesnt change spring rates or anything like that, competition drift guys actually run softer than you'd think rear spring rates to get more drive out of corners so they can outrun the chaser or catch the leader in tsuisou battles. proof of the success of his setup was his 3rd place in his first JDM event there in the R33

now BACK ON TOPIC!

if u want more caster in your gem front end, why not swap the left and right UPPER control arms?? i've heard this is a good trick, havnt tried it myself yet to know for sure. somewhere around 8 degrees caster would be sweet for assisting the steering to return lock to lock with minimal assistance from the driver.

more steering lock? modify the rack to move further side to side, and as mentioned before modify the steering lock stops, carefully, and keep an eye on wheels clearance, especially when suspension is compressed, not just at normal ride height, or you'll tear tyres out on the inner sidewall when u loop it over ripple strips, like i did last time at QR..

PS ackerman really has no great benefit at speeds over 30 kph, its just to assist grannies parking in tight spots. getting rid of ackerman could be beneficial to an out and out drift car.

cheers, dave.
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archangel62
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Post by archangel62 »

redzone (coxy) wrote:if u want more caster in your gem front end, why not swap the left and right UPPER control arms?? i've heard this is a good trick, havnt tried it myself yet to know for sure. somewhere around 8 degrees caster would be sweet for assisting the steering to return lock to lock with minimal assistance from the driver.

...

PS ackerman really has no great benefit at speeds over 30 kph, its just to assist grannies parking in tight spots. getting rid of ackerman could be beneficial to an out and out drift car.

cheers, dave.
I've done a hell of a lot of head scratching about this, and I've figured out why castor actually makes a car handle better, rather than just making the steering centre more. Consider like, a MASSIVE amount of castor, like 30 degrees. Imagine the upper balljoint being like, 10cm back or something. Now imagine what would happen if you had 90 degrees of castor. The steering would pivot at right angles. "Steering" would just camber the wheels, both to the left, or both to the right. Now lets go back to that 30 degrees. Two thirds of turning will actually turn the wheels, whilst one third of the turning will be cambering the wheels into the corner, both sides.

Obviously you don't want 30 degrees of castor. But imagine that principle with 8 degrees of castor - you turn at 10 degrees at high speed, you get what, like 0.9 degrees of camber into the the corner, on BOTH wheels. The crux of camber is that one wheel's camber helps, the other hinders. But camber generated by castor is in the right direction on both wheels, which is just awesome. Even though 0.9 degrees of camber isn't a lot, consider the maximum camber a stock Gem can get is like -1 degree, so another -0.9 on both wheels at once should get noticeably more turn in.

Only catch is it does the opposite when you're countersteering, both wheels camber out of the corner, effectively positive camber. The other thing is castor will marginally decrease your peak turning angle (steering lock) even though the steering wheel will physically turn the same amount.

As for the ackermann, I can imagine it helping on lower speed corners, and helping slightly even on higher speed corners, but yeah once you're countersteering the ackermann would just have a stupid effect and yeah, make things worse. Good call.
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Post by insane gemini »

hey has any one done any thing to there gems with all this info. i just bought a ca18det to put in my coupe and i want to drift it and i would like to do all the mod to help it drift.
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